


Forever is an Ambiguous Concept

by agentverbivore (verbivore8642)



Series: Forever AU [1]
Category: Agents of S.H.I.E.L.D. (TV), Forever (TV)
Genre: (rating is cautious), ABC Network-level blood and gore, Alternate Universe, Alternate Universe - Police, Blood and Gore, Blood and Injury, Crossover, Enemies to Friends to Lovers, Enemies to Lovers, F/M, Fitz & Trip are partners, Fitz's POV, Forever (ABC) AU, Gen, Immortality, Implied/Referenced Character Death, Jemma's POV, Kissing, Making Out, Medical Procedures, POV Multiple, Police Procedural, Temporary Character Death
Language: English
Status: Completed
Published: 2015-01-07
Updated: 2015-01-21
Packaged: 2018-03-06 10:18:00
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 14,769
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3130880
Author URL: https://archiveofourown.org/users/verbivore8642/pseuds/agentverbivore
Summary: <blockquote class="userstuff">
              <p>Jemma Simmons is the finest medical examiner New York City's ever had, and Leo Fitz, an engineer for the NYPD's new tech division, is fascinated by her - and is convinced that she's hiding something.</p><p>What Fitz doesn't know, though, is that Jemma <i>does</i> have a secret: She can't die.</p>
            </blockquote>





	1. Going to the River

**Author's Note:**

> Characterization Note: Jemma is almost two centuries old, so if she seems somewhat unlike show!Jemma, that's why. She's had about two hundred years to practice lying and getting out of sticky situations, and she's gotten _much_ better at it.
> 
> Copyright Notes: I used the pilot of _Forever_ heavily in writing this installment - much of the medical and case jargon comes directly from the show, and for that I take no credit. Any adjustments thereof are mine, and any of the personal plot aspects are of my invention. 
> 
> Plot Notes: There's a fair amount about the original premise of _Forever_ that just plain doesn't make sense. I made tweaks here and there to make it more "believable," relatively speaking, but anything about Jemma's condition that doesn't seem logical is entirely thanks to the show. I've left things I couldn't quite explain away, and, well - let's just hope you guys can suspend your disbelief anyway. :-)
> 
> Ratings Note: T for a certain amount of blood/gore. Read cautiously if you're squeamish, particularly the opening paragraphs.
> 
> It's not necessary to have seen any of _Forever_ to read (and hopefully enjoy) this story - although I will say that the entire thing came into being as I watched and giggled to myself over how similar Jemma is to their main character.

 [](http://verbivore8642.tumblr.com/post/107453446515/forever-is-an-ambiguous-concept-a-fitzsimmons)

\------

 

_Tonight_

 

One moment, she was chasing the suspect down an alleyway, and the next, a Lexus sedan came crashing into her, one wheel rolling jaggedly over both her legs as it fishtailed and sped off into the night. Excruciating and familiar pain radiated from the broken femurs up to where she was fairly sure a rib had skewered her intestines, meaning that the warm blood soaking through her clothes would reach a terminal volume in a matter of moments.

The last thing Jemma Simmons took note of before dying was a horrified shout from somewhere behind her, Scottish accent breaking in fear, two bright blue eyes swimming above her as her vision finally faded out.

\-----

Five seconds faster. Five seconds, and Leo Fitz would have been able to reach for Simmons before the Lexus struck her. The car roared away from him, but he didn’t care who was in it or that the suspect was getting away, all of his thoughts now focused on the broken, bleeding body of the most interesting woman he’d ever met.

He thought he shouted her name as he came skidding to a stop and dropped to the concrete, hands immediately coming up to skim over her, wanting to do something, anything to stop the flow of the blood that was pooling rapidly around his knees. But Fitz wasn’t a doctor, he was leaning over the doctor, the beautiful doctor that he thought he might – a choked sob escaped and he fought against the wave of nausea threatening to claw its way up his throat.

“Can you hear me? Jemma, God, _please_...”

He was surprised he even managed to say that much, reaching out with a shaking hand to search for the pulse that he prayed would be at least stuttering underneath her skin. No response met the gentle press of his first two fingers, however, even when he desperately put on more pressure and then tried to find her breath. Nothing. 

Fitz wrenched himself up and away from Simmons’ body and strode to the opposite wall, trying to slow the rapid, panicked breathing that was forcing its way out of his lungs. This couldn’t be happening – it couldn’t. He’d only just found her six months ago, she couldn’t die on him now; he pressed his fingers against his eyelids, trying to force himself to acknowledge that he couldn’t love this woman who was practically a complete stranger to him. 

It defied explanation, he knew, and Fitz wasn’t a naïve man – he was generally considered a genius in fact, and that meant he really did _know_ that people don’t just fall in love with coworkers at the drop of a hat. Yet finding Simmons had felt like he’d just solved the world’s most complex equation, as if the parts to a machine had just slotted together before him, and it was stupid, Fitz knew that, but right now he was standing next to her dead body and it seemed as if an entire life he’d never get to live was crumbling before his eyes. 

His foot nudged against a metal trashcan, and without thinking Fitz shoved the two nearest bins over, the loud clanging echoing through the empty alleyway as he gasped in breaths, leaning over with his hands on his knees. After he realized that there were tears on his face, one of the cans rolling to a clattering stop against the opposite wall, he sucked in a large gulp of air and blocked the well of anguish that had spilled over so quickly. Someone was dead – he needed to call 911, and then tell his partner where to find them.

Having calmed himself down by thinking of the practical steps he needed to take before he could collapse onto his own bed and allow his desperation to run its course, Fitz turned back to Simmons – only to discover that her body had disappeared.

\------

The cold shock of the late-spring waters of the Hudson was the first thing to hit Jemma when she returned to life, and this evening it was especially brisk. As her head broke the surface, she took in large gulps of air and shoved her hair out of her face, treading water and orienting herself, figuring out where she’d emerged before swimming to the closest shore.

Much to her relief, she could see headlights already waiting for her at the edge of the water, a familiar silhouette holding up a robe as he saw her approaching. Once she reached the shore, Jemma took a deep breath before emerging, wincing at the bite of the night air against her bare skin. Returning from the dead without any clothes on seemed to make sense in the weird pseudo-logic of her condition (although the number of favorite blouses she’d lost this way really was unconscionable after almost two centuries), but that didn’t make being naked any more comfortable.

“I told you nothing good would come of playing cops and robbers,” Phil said, keeping his eyes averted as she scampered into the robe he held out.

“This is the first time I’ve died in at least two weeks,” she retorted, tying the thick, white robe securely closed. He just shook his head in that irritating parental fashion to which he’d become accustomed – she’d have to remind him sometime soon that he was _her_ adopted son, no matter that her body looked as if she was half his age. “Skye couldn’t make it?” 

“A date with another one of her ruffians,” Phil grumbled, and Jemma grinned, still pleased with how well he’d taken to her assistant and friend. Considering the nomadic lifestyle they’d had to lead to hide Jemma’s apparent immortality, Phil didn’t take well to most people (although he was skilled at faking it) – but Skye had been an exception. “We need more of those heart monitors, by the way. I think there’s only a couple left.” 

“I’ll ask Skye to make the order tomorrow.”

One of the nicer things about having lived into the 21st Century was that it was much easier now for her to receive assistance and clothing after she returned. She’d had too many uncomfortable, frightening encounters in her first century to count – these days, she wore a heart monitor that sent a wireless signal to Phil, so he knew instantly when she died, or was dying, and could come retrieve her. (Or, more recently, to Skye, to allow Phil a modicum of freedom. Not that he had ever asked for it, or ever would; it had been at Jemma’s insistence that he allow Skye to take some of the burden.) Luckily, she tended to emerge in the same, large body of water nearest to whatever city in which she’d died – although that was easier to manage in New York than landlocked Las Vegas, for example, when she could pop up in any one of a hundred luxury swimming pools.

“So what was it this time? Another gunshot?” Phil waited until she’d buckled in before pulling away, the car bumping unsteadily over the rocky ground.

“Hit and run, actually. It’s been a long time since I’ve bled out – ” Jemma stopped and cringed. “Oh, dear. Fitz was there.”

Phil flicked his eyes in her direction, hands firmly gripping the sliding wheel. “And you think...”

“I’m sure he saw me die. Oh, _dear_.” Her hands flew up automatically to curl around her neck, a nervous tick that she hadn’t managed to shake in all almost-two centuries of her life.

Sighing tightly, he set his jaw, rolling the car to a stop at the edge of the paved road. “Time to pack it up. Too bad – I always liked New York. Great Shwarma.”

Jemma bit her lip, nose wrinkling as she considered their options. “No,” she replied slowly. “No, I’m not ready to leave yet.”

Phil stared at her, letting cars whizz past them on the pavement. “What’re you gonna do? He _saw_ you Jemma. If he’s as smart as you’ve been telling me –”

“He’s technically a genius with at least one PhD in advanced engineering –”

“So then I’m _really_ sure he’s noticed by now that your corpse has disappeared,” he interrupted, giving her another one of his annoyingly paternal eyebrow raises before he pulled onto the road.

Jemma took a deep breath. “I’ll have to tell him the truth.”

“You’re building up a real list of people who know your secret, you know. First Skye, then this guy –”

“Not just any guy. Fitz.” Jemma stared out at the blurred streetlights as they sped towards the highway back to the city, unsure of what exactly made her so certain about what she was about to say. “I trust him.” 

After putting her trust in more than one wrong person over the long course of her life, she’d developed something of an acute instinct about whom she could tell and whom she couldn’t. Normally this amounted to one person in a generation, maybe two if she was lucky. But something about the new millennia must have been good for her, because she not only had two trusted people in her life already, but also had just decided to add a third. She’d raised Phil, and Skye had fallen into her life rather unexpectedly a couple years ago – but Leo Fitz had broken all the rules and somehow convinced Jemma that she could trust him with her life after only knowing him for six months.

“Would you please take me to his apartment, Phil? I owe him an explanation sooner rather than later, I think.” 

\------

After a quick stop at a gas station to allow Jemma to change into the clothes Phil had brought, he drove her to the apartment building in which Fitz lived. It was one of the few of its kind left within Manhattan itself, slick skyscrapers dwarfing the squat, eight-floor building, wrought-iron fire escape casting shadows across the art-deco façade. As she hiked up to the fifth floor of the elevatorless building, she remembered visiting New York back when this type of architecture was all the rage, leaflets advertising their style and luxury littering practically every sidewalk and gutter within the city proper. That, of course, had been a very long time ago. These days, there were just a few of these relics left in New York. Some rotted in outward corners of the city, and others – like this one – had been just barely renovated enough to allow modern conveniences, but still had fifty-year-old wallpaper cracking along the staircase.

Jemma had only visited Fitz’s apartment once before, but she remembered the distinctive thistle-shaped knocker affixed below the peephole. (His mother had given it to him when he first moved in, he said, and he hadn’t the heart to take it down – although Jemma suspected he was rather fond of the thing no matter what he asserted to the contrary.) Sweeping her wet hair over one shoulder and wiping her hands on her jeans, Jemma gave the metal ring two sharp taps and then stepped back, deciding that it would be better to allow him a little distance to accept what he was seeing. 

Sounds of glass clinking and then a muffled swear were just barely audible before soft footsteps approached and the door swung inwards, revealing a very disheveled Scottish engineer holding an unopened bottle of Macallan by the neck. It took him a few seconds to register what he was seeing, and Jemma could pinpoint the exact moment when he did so, his red-rimmed azure eyes widening and mouth dropping open. The scotch slipped from his fingers to drop to the carpeted floor with a loud thunk, and she couldn’t help the wince that crossed her face as she instinctively braced against the glass breaking.

When Fitz still hadn’t said anything, Jemma gave him a shy smile and tucked a loose, damp strand of hair behind her ear. “I suppose you’ve got a few questions.”

 

\------

 

_Approximately Six Months Ago_

 

“You better hope they take a while to get all those bodies to the awkmee, Jems,” Skye said, pulling the car onto the highway. “Otherwise they’re gonna notice that both the M.E. and her assistant have simultaneously disappeared without warning.”

“How many times do I have to tell you not to call the O.C.M.E. the ‘ _awkmee_ ’? Simply ‘the office’ would suffice,” Jemma grumbled into her lap, curled over her seatbelt as she tried desperately to towel-dry her hair while her friend drove, inwardly cursing her own terrible luck. “It was an utter bloodbath, Skye. I haven’t seen anything like it in years – and haven’t _been_ in anything like it in decades. They’ll be another few hours before delivering the bodies to us.”

Although she did own the car, it was essentially reserved for Phil and Skye’s use to come find her post-rebirth, so – like most New Yorkers – Jemma took the subway into work every morning. Today’s ride had been more eventful than any of the hundreds she’d taken since returning to New York three years prior: After a few stops, the train crashed headlong into another one, and Jemma found herself violently run through by a metal bar, fading into death along with the dozen-or-so other passengers in the car with her. Unlike those poor people, however, Jemma awoke in the Hudson moments later.

“That’s a new experience for the books though, huh?” Skye kept her eyes mostly on the road, gum snapping cheerfully as she spoke. “You’ve never died in a subway crash before.” There was a slight pause, and Jemma continued trying to wriggle her bra on underneath the large robe. “Or have you? I’m starting to lose track.”

Jemma laughed, reaching back to grab her new blouse. “No, never in a subway crash. I have been impaled before, however.”

Skye waggled her eyebrows and grinned. “Miss Simmons, I never.” 

A groan, and Jemma whacked her friend on the shoulder. “You have a _terrible_ sense of humor.” 

“Cultivated in the finest orphanages and foster homes the five boroughs have to offer,” she deadpanned. Although it had been meant lightly, discussing Skye’s lonely childhood always made Jemma sad. Not that she could do anything to change the past, no matter how much of it she had lived – and, frankly, Phil had been more than enough of a handful for her.

Adoption had never been something she’d actively sought out, in keeping with her attempts to avoid too many emotional connections and the pain of their inevitable deaths. But she’d found herself roped into a health lecture at an orphanage in Los Angeles in the 1960’s, and as she waited in the parlor she’d spotted a toddler fiddling with a collection of playing cards torn from dime-store magazines. He was small for his age, but his brow furrowed in intense concentration as he tried to explain why Captain America was the leader of his little card collection in disjointed, childish English. Something about his earnestness and evident isolation pulled at Jemma’s heartstrings, particularly when she noted how his supposed caretakers were neglecting him – and saw the unsubtle slap one of them gave him when discovering that he’d been bothering a guest. Before she knew it, she was signing adoption papers and tucking the superhero playing cards safely into her purse. It had probably been the most rash decision she’d ever made – and for someone who’d lived as long as she had, that was saying something. 

The sweet little boy who would spend hours inventing adventures for his squad of superheroes eventually grew into a frustratingly rebellious and rambunctious teenager, however, and, as much as she appreciated Skye’s friendship now, Jemma couldn’t imagine taking care of another child after having been exhausted by Phil. Although his chosen profession hadn’t made her worry about him less – Private Investigators aren’t known for their relaxed lifestyles – at least these days he channeled his recklessness into work. 

“You know, I think I may have been gone for a few seconds longer this time,” Jemma mused, fastening the button on her suit trousers. “I just wish I could keep a stopwatch on me through the rebirth, I can’t get _any_ solid data this way. And I think my mother’s broach came off during the crash.”

Skye whistled. “Gonna have to grease some palms at the station to get that back.” 

Jemma groaned and settled into her seat, having done all she could with her appearance until she got to a restroom. Most of the city’s police precincts weren’t especially fond of her – it seemed they didn’t like being corrected on their misleading medical information in the middle of televised press briefings.

\------

Fitz had eventually gotten used to the idea of being out in the field, despite the fact that he would much rather have stayed in the labs of the new advanced tech division to continue working on his federal R&D grant. Being able to work with Trip was a particular boon, since he was the only detective in the NYPD that Fitz didn’t find completely boorish. But beginning their second week on the job together by examining mass casualties at a freak subway crash, and then spending what might be a rather long time at the Chief Medical Examiner’s office with more dead bodies, did not have Fitz in the best mood. 

“C’mon man, you had to have dissected at least one animal in school,” Trip tossed behind him as they strode down the immaculate, white hallway towards the O.C.M.E..

“Exactly one animal, yeah, I did,” Fitz grumbled back, crossing his arms and wishing he’d been able to sneak off to inspect the train’s engine for faults. 

Trip paused at the end of the hall and grinned back at his partner. “Passed right out, huh?”

Shoving the door open, Fitz huffed. “I made it through the whole thing, thanks very much. Couldn’t look at my neighbor’s cat the same way again, though.” He turned around just before knocking into an empty steel mortuary table, and suddenly his entire mouth dried up.

When they’d been instructed to go to the Chief Medical Examiner for this case instead of their precinct’s normal M.E., Fitz had expected some stuffy old man who’d been examining corpses for longer than both he and Trip had been alive combined. Fitz had most certainly not expected to see a gorgeous woman in her mid-twenties leaning thoughtfully over a dead body, brown hair tied back and buttoned lab coat hugging her hips in a way that couldn’t possibly be department sanctioned.

Completely unfazed, Trip brushed past him and Fitz shook his head, berating himself for being such an idiot. Rule one of being a good human being – do not objectify one’s co-workers, especially not upon first meeting them. Even if they do meet a variety of lab coat fantasies you’ve been harboring since you were a teenager.

“C-5. Cervical fracture – died of asphyxiation,” the M.E. called out, surprising Fitz once again by having an English accent. That the city’s _Chief_ Medical Examiner was so young was surprise enough – the fact that she wasn’t an American just added even more fodder to Fitz’s burgeoning interest.

A lanky young woman with her hair messily pulled into a bun and red Cons on under her scrubs finished making notes on her clipboard and then tugged a sheet back over the body. Once that was done, Trip made their presence known, reaching his hand out.

“Detective Antoine Triplett, from the 84th.”

The M.E. turned in their direction and gave Trip a smile that could stop any subway train in its tracks. “Of course, they said you’d be coming by.” Pulling off her latex glove, she grasped Trip’s hand. “Jemma Simmons, Chief Medical Examiner.”

Trip gave her a quick smile in return. “Captain says you’re the best the city’s ever had.”

Something dark flashed across her face, but disappeared with another one of her blinding smiles. “I very much doubt that, Detective. New York’s been around rather too long to make that assertion.”

Nodding amicably, Trip turned back to Fitz, who snapped his jaw shut as quickly as possible. “This is my partner, Leo Fitz. He’s from the tech–” 

“The initiative to incorporate advanced technologies for the improvement of our law enforcement practices,” Simmons rattled off. “I have read _all_ about the 84 th.” She stepped around Trip to reach her hand towards Fitz. “I think it’s an excellent idea – the more brainpower on the street, the better. What’s your specialty?”

Fitz swallowed and gave her hand a good, firm shake, trying to use the momentum to stave off his nerves. “Engineering, but I work mostly with nonlethal weaponry and robotics.”

Her eyes lit up. “Oh, fascinating. I’d love to pick your brain about that sometime –” She eyed the covered corpse on the table nearby. “Not literally, of course.” Giving his shoulder a congenial pat, she strode back to the table she’d been approaching when they entered. “Skye, who do we have next?”

The assistant, who apparently had the kind of name normally reserved for animated characters, flipped over a few pages in her chart and lifted the sheet away from a new body. “Subway conductor.” 

Trip followed them to the table and gave his partner an unsubtle ‘come _on_ ’ eyebrow raise. Squaring his shoulders and promising himself that he wouldn’t get nauseous this time, Fitz shuffled over to the table, hanging a couple feet back to hedge his bets. 

“That was some impressive diagnosing you did before,” Trip mentioned, staring down at the heavyset conductor like he was just another piece of furniture. “On that woman? Didn’t look like you’d even cut her open. How’d you do that?”

Simmons gave him a casual shrug, sliding on a pair of goggles. “Educated guess.”

“D’you have a cause of death yet?” Fitz winced at the sharpness of his tone, but the smell of the bodies, even as faint as they were with the flesh still unopened, was starting to get to him.

“Only about twenty,” interjected Skye with a small chuckle. “Spinal fracture, blunt trauma to the head, tracheal exsanguination, all post-mortem. I’m guessing that cardiac arrest got ‘im first, but...” She trailed off at the eyebrow raise of her boss, and grinned awkwardly, cocking her pointer finger. “You’ve got this. I’ll just hang over here and, uh, take notes. Quietly.”

“I was just about to begin my official examination,” Simmons explained, snapping on new gloves. “You’re welcome to stay.”

“Wouldn’t mind hearing C.O.D. from the horse’s mouth.” Trip crossed his arms, settling in to watch, which meant that Fitz had to decide very quickly how to proceed from here. If he watched, he was almost certainly going to hurl right over the evidence, as well as the very pretty medical examiner. But if he left, Trip would tease him for the rest of eternity – and the very pretty medical examiner would think he was a right numpty. Neither option was acceptable, so Fitz settled for staring vaguely around the room, eyes settling on the variety of frightening-looking devices that were the bread-and-butter of this morbid profession.

“If you’d like to ameliorate some of the smell, we keep the vapor rub on that shelf,” Simmons added, picking up an unnervingly large saw.

Swallowing his pride, Fitz reached for the jar of yellowish goop while Trip continued to watch her work. “You’re not using any,” the detective said, keeping his eyes pointedly on the M.E. rather than the body. Fitz heard her make the first incision in the corpse’s chest and cringed, screwing the jar lid back on.

“I’m accustomed to the aromas of death.” Simmons worked quickly and efficiently, examining the relevant organs and calling out notes to Skye, who seemed unnaturally blasé about the whole endeavor. Fitz was just proud that he managed to keep his morning snack down. 

“I’m afraid this kind of work isn’t good for a queasy stomach,” Simmons noted nonchalantly, glancing up at Fitz as she switched her attention to the lower organ cavity. 

The other two turned to stare at him, and he dropped his mouth open, ears flushing pink. “I – don’t – I don’t know what you’re talking about.”

When she looked away from her work this time, she gave him an understanding smile. “You’ve had your hands balled into fists from the moment I picked up the bone saw, and you haven’t looked straight at me or the table since. It’s perfectly natural –”

“I don’t have a queasy stomach,” Fitz griped, crossing his arms and moving to stand right next to his partner. He couldn’t bring himself to look down at the body, but he did make eye contact with Simmons, who raised an eyebrow in faint amusement.

“Well, here’s something.” The medical examiner used forceps to remove a bloody, grayish mass from the stomach, lifting it quickly to her face to take a quick whiff. Unable to help himself, Fitz gagged, holding a fist to his mouth and fervently thanking the inventor of Vick’s vapor rub ( _presumably someone named Vick_ , he thought wryly). Either because she was so engrossed in her work that she didn’t notice or out of kindness, Simmons didn’t comment on his reaction.

“What is that stuff?” Even Trip’s face was twisted into a look of deep disgust, which made Fitz feel slightly better. 

“I believe it’s sausage. Probably his last meal.” She lowered the meat into a nearby metal tray and returned to the body. “Greyish tissue in areas of the myocardium, plaque formation in the aortic arch, and an apparent love of fatty breakfast meats. If this man had lived any longer, he almost certainly would have died of a heart attack.”

“So he didn’t die of a heart attack?” Fitz’s voice was pinched, but he managed to get the question out loud enough that it was mostly audible.

“Of course not,” Simmons tsked, looking up at them. “Didn’t you see the sausage? I would estimate he ate his meal between one to two hours before the accident.”

“That would’ve been more than enough time for the hydrochloric acid to break down the food,” Fitz muttered, and she gave him a pleased nod.

“Yes, precisely,” she said. “Unless something slowed down his digestive process. And, here –” Simmons traced her finger through the chest cavity. “Blistering around his lungs. He died of pulmonary edema.”

“So that’s our cause of death?” Trip pulled his notebook out, but she shook her head before he could uncap his pen.

“No, that’s the _manner_ of death. In the sense that if you get shot in the head, you technically die of –”

“Brain herniation,” Fitz interjected, and then sighed inwardly, berating himself for trying to show off. At least his answer was right (of course it was), and she nodded over at him again.

“ _Cause_ of death is different. I believe this man was poisoned.”

“Hold up,” Trip said. “You’re telling me that this was a homicide?” 

“No, I’m saying that this was fifteen homicides.” She started stripping off her gloves and removed her goggles. “And this is just my preliminary assumption, I’ll need the tox report to confirm my diagnosis.” Turning around, she bustled over to her desk and started making notes. “But I have a fairly good track record, to say the least, if you want to begin your investigation.”

“It’s kind of crazy,” Skye said, and Fitz turned to the assistant, whose existence he had almost completely forgotten. “Sometimes she doesn’t even need to open ‘em up to know how they died. She’s like the corpse whisperer.”

“Skye,” Simmons scolded, not looking up from her notes. “I’ve told you not to call me that.”

“But it totally fits you. Kinda awesome _and_ kinda creepy.” She gave her boss a shit-eating grin, Trip stifled a small burst of laughter, and Fitz couldn’t help but raise his eyebrow in surprised amusement. If _he_ ever said anything like that to their Captain, he was pretty sure he’d find himself thrown into the holding cells before he knew what happened. 

“Now if you’ll excuse me, gentlemen, I have quite a lot of bodies to get through this morning.” Evidently choosing to ignore her assistant’s cheek, Simmons stepped around her desk to gently corral Trip and Fitz toward the door. “I’ll keep you up to date on my findings.” 

“We’ll be in touch,” Trip said, nodding his goodbye to the assistant and sweeping through the door. 

Before Fitz could follow him, however, Simmons reached her hand out for another handshake. “I’m looking forward to working together, Detective Fitz.”

“Oh, um,” he stuttered, distracted by the firm smoothness of her skin and the way her eyes shone in the office’s bright lights. “I’m not a – just Fitz is fine. No real title for engineers.”

“I’d assume you needed at least one PhD, so you could probably go by ‘doctor,’” she said, smiling. “But Fitz it is. You can call me Jemma.” 

He realized then that he was still holding onto her hand, and pulled away rather abruptly, lest he demonstrate his attraction to her any more obviously. “Yeah, um, got to –” Fitz gestured vaguely in the direction that his partner had disappeared. “Nice to meet you, Simmons.” 

Then he was out the door, shaking his head at himself as he jogged to catch up with Trip.

Really, if this were a cartoon he’d be hitting his head against the hallway wall right about now. Fitz may be the most respected engineer in the entire division, possibly the whole city, but somehow that didn’t translate to being able to interact with people – even if said person was probably smarter and more intriguing than anyone else he’d met in New York.

\------ 

Jemma wrinkled her nose, watching the door swing shut behind the engineer. Well, that was that – no new friend to be made there. When he’d first walked in, she’d been incredibly curious to learn more about the kind of scientists chosen to work with the 84th, which had only started its advanced tech initiative a few weeks prior.

Being rather supremely observant, she could tell immediately which of them was the detective and which was the consultant, and had been instinctively drawn to the shorter, curly haired man as a result. Fitz had to be incredibly intelligent to be chosen to go into the field, and she couldn’t resist wanting to interact with such a person. It also didn’t hurt that she’d always had a weakness for Scottish accents, which she had certainly not been expecting. But he’d spent the whole visit at a distance, only speaking once she’d unintentionally gotten his hackles up about his stomach, and his refusal to accept her congenial offer to call her by her first name just cemented her suspicion that he had no interest in being friends. 

Not that it should bother her much; she could learn about the 84th from his more amiable partner, and she shouldn’t want to spend more time studying his fascinatingly blue eyes anyway. That just invited the temptation for her to break her own no-more-attachments rule, and the surly Scottish engineer wasn’t going to make Jemma give into flash impulses that easily. So what if their interactions were limited to working on this one case? That was fine by her; then she could return to her normal C.M.E. duties that much faster. 

“Wish all the detectives they sent us were that cute.” Skye had already moved to typing up her notes on her laptop, feet resting on the edge of one of the examination tables, and gave Jemma a pointed eyebrow raise. 

“That’s inappropriate, Skye,” Jemma replied, possibly a little more sharply than she should have.

“Like you wouldn’t mind getting a little inappropriate with that tech guy,” she shot back. “C’mon, I saw you checking him out.”

Jemma pursed her lips. “You know my rule about dating better than almost anyone else.” 

The sigh that escaped Skye’s mouth was more than a little sad. “Just – almost two _centuries_. Seems really lonely.” 

“More than you could imagine,” she whispered to herself, taking care to keep those feelings locked up tight. “Anyway,” Jemma said loud enough for Skye to hear. “You are right that his partner is very visually appealing, with a particularly symmetrical face. Based on his low body fat percentage, I suspect that he spends a fair amount of time exercising –”

Skye giggled and wagged her finger in her boss’s direction. “Hey, I’ve already got dibs on that tall drink of water – you keep your curmudgeonly hands off.” 

Chuckling at her friend’s seemingly endless sexual appetite, Jemma shook her head and raised her hands in pretend defeat. To be honest, the detective wasn’t really her “type,” as they called it these days, anyway. With plenty on her plate at work and a son to take care of, Jemma hadn’t been in a real relationship in years, the general lack of suitable prospects making adhering to her no-dating rule that much easier. Every so often she’d go on a few dates – just enough to take care of her own needs – but having more that that wasn’t a priority. Using the tools provided to her by her job to find a way to restart her aging was far more important – and achieving that was the only way she’d ever let herself truly date again. She was tired of watching loved ones die.

The atmosphere in the O.C.M.E. back to normal, Jemma returned to examining the train passengers, exploring their deaths in a way that she could never quite do for her own.


	2. Take the Longer Way

“Phil!” Jemma shouted into their shared townhouse, shrugging off her coat and plucking the blood sample from her bag. “Phil, are you here?”

He poked his head out from the sitting room, white shirt-sleeves rolled up to his elbows and tie looking slightly more disheveled than usual. “Yeah, just got done with that surveillance case. What’re you doing home?”

She strode past him, knowing that he was about to seriously object to what she said. “I need your help in the lab. I’ve just had a rather interesting idea about how I can determine the poison used in my current case.” 

Phil’s eyes widened. “No.”

Turning around at the doorway to the basement, Jemma grinned. “Yes.”

A few minutes later, she was lying strapped to her primary exam table in her most modest underwear – no point in scarring her son any further, after all, but she wanted to try to avoid losing more clothes than necessary – while Phil fiddled with the vitals monitoring system. The lab itself was actually their converted basement, and, thanks to the savings she’d accumulated during her long life, it had all the lab supplies she required. She didn’t often use said supplies to induce her own death, however, and she was taking a fairly large amount of amusement in seeing the room from a new angle.

“I should really think about putting in new tiles – these are ghastly.”

“Are you sure you want to do this?” Phil flicked the syringe Jemma had prepared with the subway conductor’s blood, his normally steady hands trembling slightly. 

“It’s the only way to know immediately what he used,” she replied, tone brusque. She watched him eye the syringe, noted how his jaw tightened, and resisted the urge to reach for his hand. Some days, when he scolded her for her recklessness, or made dinner with only organic ingredients, or talked about one of his cases, she almost forgot that Phil was the same little boy she’d found sitting alone in that orphanage all those years ago. Almost forgot that, as he once put it, she was the first person to ever give him a chance. “Whatever pain there is will be fleeting, Philip,” she murmured, and he met her eyes.

Seemingly shaking sense back into himself, Phil nodded stoically, and lifted the syringe to the inside of her elbow. “Ready?”

Jemma gave him a smile and then nodded. “Here’s to the unknown.” 

Breathing deeply through his nose, Phil carefully injected the blood into her vein and then stepped away, folding his arms across his chest. Within seconds, the monitors attached to Jemma started beeping loudly and a searing, wrenching sensation devoured her body from the stomach outwards, fingers tingling in pain and lungs burning until, finally, the familiar dark consumed her.

What felt like moments later, Jemma burst through the surface of the freezing cold Hudson, pulling air painfully into her straining lungs. That first breath is always the worst, she thought, treading water and sweeping hair out of her eyes so she could orient herself. After what turned out to be a lengthier swim than normal, she had to wait a few minutes for Phil to find her, grateful that she at least had managed to find herself alone at the shoreline by an abandoned warehouse.

“Aconite!” Now seated happily in the passenger seat and warming up in her traditional cotton robe, Jemma recounted her findings to Phil, whose general demeanor was only slightly more subdued than usual. “Extremely fast acting, and attacks the gastrointestinal system – which explains the sausage.”

Phil gave her a sideways glance as he flicked on his turn signal. “The sausage.”

“That’s not the point.” She started shimmying into her work clothes as they talked, knowing that she’d have to run back to the office as soon as they returned to the house.

“The point is – aconite.” 

“Precisely. It’s derived from the plant _Aconitum_ , more commonly known as monkshood.”

“Easy to find?”

“Unfortunately, yes. Interestingly enough, aconite is also often used as an herbal medicine to prevent pain in China.”

Turning onto the exit closest to their house, Phil raised an eyebrow. “As in, ‘here, let me rub this potentially lethal substance on your sore ankle?’” 

Jemma shrugged. “I suppose you better trust your doctor.” Wringing her hair tightly in a towel, she made a small grumble of annoyance. “I might as well give up on styling my hair altogether these days. Maybe I should just cut it all off.”

Phil laughed; this was a familiar complaint. “You’d look good with short hair. Very Mary Tyler Moore.”

Chuckling, she shook her head. “Well, that’s that, I am _not_ getting my hair cut like the object of your teenage fantasies.” 

The look on Phil’s face was worth the potential emotional scars, mouth gaping open and eyes widening in innocent horror. “She was not –”

“We are not having this argument,” Jemma teased lightly, pulling a brush through the tangles. “I used to clean your room, remember?”

Phil shot her a quick glare and turned back to the road. “I just meant that you’re both unnaturally cheerful and small birds help you dress in the morning. That’s all.”

As they rounded the corner of their street, flashing police lights strobed against the bricks of the buildings’ façades, and Jemma had the sinking feeling that her decision to work on a case that involved one of her own deaths was about to backfire spectacularly. 

“What the...” Phil trailed off as he pulled into an empty space, and Jemma’s stomach clenched as she saw Detective Triplett stride out their front door.

Leaving Phil to finish parking, Jemma hopped out of the car as she finished up the last few buttons on her blouse, and jogged across the street. Before she could get far, however, a familiar figure blocked her way.

“We have some questions for you, Simmons,” Fitz said, arms crossed defensively over his chest. Something more genuinely suspicious than Jemma would have expected flickered behind his eyes as he studied her, and she decided to tread the path of least resistance for the moment.

“Very well, since it appears that my house is currently unavailable,” she replied. “Lead on, Fitz.”

 

\------

 

Feeling completely out of sorts, Fitz stood in the observation room, staring through the one-way glass at Simmons. She seemed entirely at ease, despite having been intentionally left alone in the interrogation room to stew for over half an hour. It was one of Trip’s preferred pre-interrogation techniques to make the suspect nervous, but all it seemed to have done was allow the medical examiner to relax, pulling her damp hair through her fingers as she gazed at the concrete wall opposite her. 

Realizing that he was clenching his jaw, Fitz forced the muscles to loosen and tried to figure out why he was so unnerved – by his own discovery, even. After leaving the O.C.M.E. that afternoon, Fitz had retreated to his lab to examine the subway’s CCTV footage while Trip looked into the subway conductor’s background. Unfortunately, it hadn’t taken Fitz long to discover something completely unexpected: Footage of Simmons stepping onto that exact subway car only a few stops before it crashed.

As if that wasn’t enough, the video clearly showed her wearing an ornate enamel broach that had been located during the forensics sweep of the train wreckage, making it even clearer that Simmons had been on that train when it crashed. Not only had she somehow managed to survive the crash without any injury – and escape the crowds without being questioned by the police – she had neglected to tell them this when Fitz and Trip were at her office this morning.

The fact that she seemed to have changed her clothes in the middle of a workday also struck Fitz as odd, despite her assertion that she’d gone to the gym during lunch and showered. Typically, people who went to the gym during the day made an effort to return their appearance to normal afterwards rather than leave their hair damp.

The door swung open and Trip poked his head in. “The Captain will be here in a minute. Ready to go in?”

Tearing his eyes away from Simmons, Fitz nodded. “D’you mind if I take the lead on this?”

Trip raised an eyebrow as he held the door open for his partner. “You sure about that? You’ve never lead on questioning before.” 

“You’ll be there if I fuck up,” Fitz answered, straightening his collar and moving his badge so it was more prominent.

Chuckling, Trip shrugged. “Alright man. But you know that it’s against pretty much every protocol to crush on suspects, right?”

“Yeah, I do. Good thing that’s not a problem here,” Fitz shot back, swinging the interrogation room door open to prevent Trip from asking any more annoyingly on-the-nose questions.

At seeing Fitz, Simmons exhaled, leaning forward onto the rusting steel table. “Ah, so this _wasn’t_ just to give me someplace warm to wait while the police searched my home. I’d started to wonder.”

Ignoring the unsubtle note of annoyance in her words, Fitz sat across from her at the table while Trip secured the door and then leaned against it. After letting the silence shift uncomfortably between then for a minute, Fitz pulled out the small evidence bag in his pocket and slid it across the table. “This belong to you?” Simmons reached for the bag and examined the enclosed broach for a moment before nodding. “That’s strange, ‘cause forensics found it on the train this morning.” 

She gave him a rueful smile and leaned back, dropping the bagged broach into the hand he’d left outstretched on the table. “I’m afraid I wasn’t entirely forthcoming when we met.”

“Never would’ve guessed,” muttered Trip from his deceptively relaxed pose by the door. 

When she spoke, her voice was appropriately hesitant, but there was something underneath it that Fitz couldn’t quite place – it wasn’t rehearsed, exactly, but almost too believable. “I take that line every morning to work, and sometimes men on the subway can be... difficult. When one man stared at me for two stops too long this morning, I moved a few cars down, and after the crash I ran out with everyone else to get to safety.”

Fitz took a moment to process her story, keeping his gaze trained on her unwavering honey-brown eyes. “And you didn’t think to share this with the police.”

“I thought of it,” she replied smoothly. “But as I didn’t see anything suspicious before the crash, I knew it wasn’t important and didn’t want to waste your time. If it was relevant I would have spoken of it immediately.” 

Turning to grab the folder Trip held, Fitz gave his partner a quick eye-roll. She was more arrogant than most of the people who came through this room by half. “As you know, we obtained a warrant for your residence.”

“I should hope so,” she quipped.

“We found your secret lair.” 

Simmons quirked up an eyebrow. “I assume you mean my laboratory. That’s not a secret, I have the requisite permits.” 

“It’s an impressive collection you have down there,” Fitz added, sliding a few glossy, color photos over the table. “Some human organs, some... torture devices.” He flipped over the relevant photograph for that last revelation, the CSI having captured what looked like a couple Victorian instruments of death, half a dozen handcuffs, and a few leather items that weren’t quite distinguishable in two-dimensions.

Peering down at the photographs, she pushed them gently back towards him with slim, steady fingertips. “Oh, those. They’re for sex.” 

An indistinct snort came from the doorway, and Fitz felt his eyes widen. Even vaguely connecting the words leather, handcuffs, sex, and Dr. Jemma Simmons made his temperature spike.

When neither of the others said anything, Simmons shrugged. “Sometimes you need to branch out.”

Clearing his throat, Fitz pushed forward another one of the photos. “We also found a large collection of hazardous toxins.” 

“All perfectly legal. I experiment with many kinds of poisons, nerve agents, dendrotoxins, algae, bacteria, etcetera, in an effort to better understand the great mystery that is death.” Her smile then put Fitz on edge, something simmering beneath her façade that he was itching to uncover. “It is, after all, my life’s work.” 

“And what if the tox report connects your lab to the conductor’s death?” Fitz watched her reactions to his questions carefully, unnerved by the impression that she was studying him just as much as he was her. 

Nonetheless, she answered without hesitation once again. “You won’t. Based on my preliminary findings, I believe he was injected with aconite. And I haven’t done experiments with aconite in many years. If I was going to kill someone, I’d use polonium – its symptoms don’t present for weeks, which would allow me time to create a better alibi.” She flashed them a quick grin and continued. “Aconite, however, works very quickly, which means that the killer had to be on the train...” Her voice trailed off, and she stared blankly over Fitz’s shoulder for a few long moments before snapping back to reality. “If you ever permit me to leave this room, I’ve just had an idea about how to collect the killer’s fingerprint.”

“We’re still not convinced you aren’t involved,” Trip pointed out. Fitz turned so that Simmons couldn’t see his face and gave his partner a ‘ _we’re_ not _convinced?_ ’ look. As much as Fitz thought there was something suspicious going on with this too-calm medical examiner, her logic was sound enough that he felt it might be time for them to look elsewhere. 

“Very well then. Say I did it.” Fitz turned back to her, observing how her hands were clasped easily in the center of the table and her eyes shining in faint amusement. “What happened this morning? Go through the hypothetical with me.”

Intrigued despite himself, Fitz leaned forward, mirroring her position. “Alright. You get on the train and dose the conductor. Gonna have to work out motive later.”

Simmons smiled. “Fair enough.”

“Then you moved to a back car and braced for the probable impact. After, you escaped in the crowd and showed up at work like nothing happened.”

“And at work, I was lucky enough to meet you,” she continued. “Really, you should have seen the look on your face – aside from being tinged slightly green. You were almost praying it was a heart attack.”

“But you’re the one who suggested poisoning,” Fitz added, turning back to glance pointedly at Trip. “So either you’re a complete sociopath who wants to get caught –” 

“Which we’re not ruling out,” Trip interjected. 

“Or the real killer is still out there...” Frowning, Fitz turned to Simmons, who just spread her hands in the universal ‘ _there you go_ ’ gesture.

“As much as I enjoy your company, gentlemen, I’m afraid you don’t have enough evidence to hold me here.” 

“Yet,” Fitz said, causing her to smile and, in turn, forcing him to suppress the desire to find a way to keep her smiling.

“Yet,” she agreed, pushing her chair away from the table. “I expect I’ll see you both again soon.” 

“Count on it.” Fitz watched Simmons leave, tapping his fingers against the table. 

Trip closed the door and then rounded on his partner. “Man, you actually believe her.”

“I’m not saying she’s completely innocent –” 

“No kidding,” Trip muttered, and Fitz tried not to let his mind wander back to those handcuffs.

“I’m just saying I don’t think she did _this_. Besides, she’s more useful if she’s out there working to clear her own name, y’know? We can keep an eye on her.”

Shaking his head, Trip turned as the door opened to reveal their boss, Captain Melinda May, who had been watching from the observation room. “I agree with Fitz.” 

Trip’s mouth dropped open. “Sir –”

“Use one of his gadgets to track her if you think she’s a flight risk, Trip, but then get back to working up alternate suspects. And I want updates on those fingerprints ASAP.” Before letting the door drop closed, she turned to stare piercingly at the engineer, who worked hard not to squirm under her gaze. “And, Fitz – keep it in your pants. There’s no interoffice fraternization in my precinct.” 

Fitz’s mouth fell open, and he could have sworn that he saw a small smirk grace her features before the door swung shut. Trip hooted with laughter, and Fitz punched him in the shoulder as he strode out of the room, muttering indistinctly about his stupid bloody genetics and fair skin.

Once back in the bullpen, Trip went off to read up on the other passengers, and Fitz was called over by Mack. The ludicrously tall man was, believe it or not, one of the precinct’s better engineers, specializing in Fitz’s areas of expertise, and they’d struck up a loose sort of friendship that mostly consisted of playing video games late at night in the lab.

“Got that info you asked for,” Mack muttered, keeping his voice low enough that any passersby wouldn’t hear. “Gotta say, even I think this is pretty fishy.”

“Yeah?” Fitz grabbed the file from him and started leafing through the freshly printed papers.

“Dr. Jemma Simmons has at least three PhDs and is highly respected – but if you go far enough back, none of the people she worked with seem to exist. Every email or phone call comes back with a ‘before my time’ kind of answer – even though she can’t be much older’n you.”

Mystified, Fitz stared at the official badge photograph attached to the front of her file. “Really? Before becoming one of the most high-profile medical examiners this side of the Atlantic, no one had ever heard of her?” 

“It’s more like everyone’s heard of her, but no one knows her.” Mack just shrugged. “That’s what the data says, anyway. Hard to find reliable references these days, I guess.” He clapped Fitz on the shoulder and sauntered off towards the lab. 

Fitz spent another few moments standing in the middle of the bullpen, staring at the picture of the gorgeous English scientist with more secrets than PhDs, desperately curious about what exactly was hiding behind the name “Jemma Simmons.”

 

\------

 

_Three Days Later_

 

Somehow, every day working with Leo Fitz was more exciting than the last, and Jemma had the niggling suspicion that she hadn’t really _lived_ as much in the past century as she had in the past three days. Of course, she had died more frequently, too, and tonight wasn’t shaping up to be much better. 

During the mess of the afternoon’s most recent case revelations, and in between her and Fitz’s bickering about aerosol versus groundwater poisoning, they’d determined that the suspect was planning on gassing Grand Central Station with a variation of aconite. While Trip had been organizing an evacuation of the station – no mean feat on short notice – Jemma had deduced that the killer was most likely on the station roof, where the ventilation shafts were open to the air, and sprinted up to try to catch him. Despite her not having told anyone where she was going, and ignoring all of her protests, Fitz had followed quickly behind her – and then promptly found himself knocked unconscious by the jittery man holding the aerosol release button.

“No one would admit that it was a safety fault that caused her death! A few grand to shut me up and that was that. Bet they’ll be sorry for that, now that I’ve put their money to good use,” sneered Koehler, the suspect they’d been chasing. He was holding a gun in his other hand, and it kept slipping in his sweaty palm.

“Please, Mr. Koehler,” Jemma said, her voice steady and hands held outstretched to show that she meant him no harm. “I know how you feel. To lose someone you love and want to bring the world to its knees for the pain you feel. Just so they see what you went though – so they understand. But killing these people won’t make it stop hurting. Please don’t do this.” 

Koehler shook his balding head, and Jemma glanced over to where Fitz was lying, unconscious, right next to the machine that would spray aerosol poison into the station. If Koehler hit the button, the station might be empty – but the engineer would certainly die.

“You’re not going to change my mind, girly, no matter what you say.”

Having exhausted her diplomatic options, she gave a brusque sigh and stood up straight. “I can’t let you do this.” 

“I think you’re forgetting,” he snapped, waving the gun in her direction, “that I’m pointing a gun at you.” 

Jemma rolled her eyes and started striding towards him. “This may come as a surprise, Mr. Koehler, but getting shot isn’t actually the worst way to die.”

His nerves clearly getting the better of him, Koehler’s finger slipped onto the trigger and managed to get a round off straight into Jemma’s stomach, driving all the wind out of her lungs and forcing her to the ground. Koehler dropped both the gun and the aerosol release button, though, and scrambled after the button, clearly not a natural killer. Having been shot many times before didn’t make it any more pleasant now, and Jemma struggled to get her limbs back under control – she only had moments to act and save Fitz from a painful, permanent death.

Gritting her teeth and ignoring the sadly-familiar searing pain of burning metal twisting apart her gut, Jemma took one last look over at the engineer, who had just started to move, coming slowly back into consciousness and blearily blinking those striking blue eyes of which she’d become so fond. “See you in a few, Fitzy,” Jemma muttered to herself, and then threw herself at Koehler just before he got to the release button, toppling them both over the edge of the roof.

 

\------

 

Head swimming, Fitz wasn’t sure if he was having another one of his annoyingly vivid dreams when he opened his eyes to see Jemma Simmons’ face hovering above him. At the first sign of his return to consciousness, she smiled. Nope, definitely not one of his dreams – this Simmons was wearing clothes, first of all, and didn’t have a lab coat. A streetlamp cast beams of light through her hair, creating an urban sort of halo around her head, and Fitz just barely stopped himself from reaching out to her.

“It lives,” she teased gently, unwrapping a blood pressure cuff from his arm. The sound of her voice made him both giddy – or maybe that was the head injury – and annoyed – because his subconscious refused to let go of this crush no matter how aggravating she was. Although, currently, she was just being rather doctor-y, pulling at his eyelids without so much as a warning and shining a bright light to check his pupil responses.

“What happened?” His voice came out groggier than he felt, and she raised the back of the gurney on which he’d apparently been passed out as he struggled to sit up.

“To summarize,” Simmons began, tucking away her examination implements. “You were knocked out, I struggled with Koehler for the aerosol remote, and he fell off the roof.” 

Her words triggered a vague and blurry memory, and a surprisingly sharp twinge of fear and adrenaline that the image had brought at the time. The dark roof was hazy, two figures silhouetted against the sole electric light. One of the figures dove at the second, and both of them fell, disappearing abruptly from sight – but as the bitter taste of bile flooded Fitz’s mouth so went the rest of the memory. Or had the first figure ducked behind the wall as the second one fell?

Fitz rubbed the back of his neck, squinting up at Simmons’ placid face. “Y’know, I would’ve sworn I saw you fall, too. Off the roof.”

She laughed, squeezing his arm. “Oh, absolutely. It’s a good thing I can sprout wings from my shoulder blades, that does come in handy in such situations.”

He studied her, the answer too smooth – her answers were always just a little too smooth for someone who didn’t otherwise seem like a natural liar – and noticed that her hair was pulled back, when before it had hung in loose curls around her shoulders. The only reason this occurred to him is that he’d wondered vaguely as they waited in the station earlier that evening whether her hair was as soft as it looked, and then berated himself bitterly for the thought. A trickle of water ran down her neck, shining in the yellow streetlight and circling blue-and-reds.

“Why is your hair wet?”

She raised an eyebrow and made a show of reaching around to feel the back of his head. “I think it may be time for an officer to take you home, Fitz. I can inform Detective Triplett that I sent you off, doctor’s orders –”

“I wasn’t hit that bloody hard, Simmons, I know your hair’s different from before.” Swinging his legs down over the side of the gurney and suppressing a wince of pain, he scrutinized her face. His fascination with the mystery surrounding her was only getting more potent by the day; Fitz was just itching to figure her out (in more ways than one). “I know there’s something you’re not telling me.”

The medical examiner rolled her eyes. “Yes, you’re right. Koehler also managed to get a shot off, but luckily he missed –”

“I don’t mean about tonight,” Fitz interrupted, determined not to let her off so easily. “I mean about you. In general. Something doesn’t add up.” 

The smile she gave him was distinctly fond, which surprised him. “If you say so.” 

Her calm was disconcerting, as was the abrupt realization that this concluded their partnership – the case was solved, and Fitz would go back to working with the boring medical examiner at the 84th precinct. He ignored the sharp clench in his stomach at that thought.

“Well, y’know I’m Scottish, and a persistent bastard at the best of times. I’ll get your secrets out of you eventually, Simmons. Time’s on my side.”

As she buttoned up her jacket, she laughed again, a tinge of darkness tainting the usually appealing sound. “I think you’ll find that is almost never the case when it comes to me,” she replied, and turned to stride away into the cool night air. “Oh,” Simmons called back from the sidewalk. “It’s been quite fun working with you on this case, Fitz. I hope we’ll get to work together again some day.”

Fitz watched her go, brows furrowing in thought. Life at the oh-eight-four was going to be far less interesting now that he didn’t have their partnership to look forward to; he liked Trip and all, but his friend wasn’t exactly what got him out of bed in the mornings.

“How’re you feeling?” Hands shoved into his jacket pockets against the increasingly chilled night air, Trip strolled up next to the gurney. Still pondering the enigma wrapped in a tight-fitting lab coat that was Simmons, Fitz gave him a noncommittal grunt and continued to stare across the street. Trip followed his gaze, and they both watched her slide into the passenger seat of a beat-up old sedan being driven, strangely enough, by her assistant. When Fitz didn’t answer, Trip just shook his head. “Man, have _you_ got it bad.”

Once Simmons was out of sight at last, Fitz blinked, having finally heard what Trip said. “What? No, she’s just – there’s something different about her.”

“Yeah, different in a ‘you desperately want to get into her pants’ kind of way.”

“I do not!” His voice was slightly higher than normal, but he barreled on anyway. “There’s something she still isn’t telling us.”

“Right.” 

“It’s a gut feeling.”

Grinning, Trip patted his partner on the shoulder. “Sure, your ‘gut.’”

“Oh, fuck off,” Fitz muttered, pulling his coat more tightly around him. 

Trip laughed, and turned away to go talk to the on-duty officers. “See you tomorrow.”

“Yeah,” Fitz said, his mind already having returned to the brilliant and mysterious medical examiner, trying to figure out exactly what he could do to learn her secrets. Preferably in some way that didn’t clue Simmons in to the fact that he’d barely been able to get her out of his head since the moment he’d met her.


	3. The Line of Great Unknowns

_The Next Day_

It was a beautiful, sunny Saturday morning in New York City, and since the night before had been particularly eventful Phil was making Jemma and Skye his famous blueberry-cornmeal pancakes. Even though technically Jemma was the parent in the household, Phil was the chef of the house – he still wouldn’t let her forget the time he came home from college to find that she only had sriracha and beer in her fridge.

Just as the second pancake of the morning landed on the floor – Skye had insisted Phil flip it onto her plate, with predictably disastrous consequences – the doorbell to the townhouse rang. Laughing at the antics of her strange little family, Jemma went to answer the door. Thanks to her general good mood (and the fact that she thought she heard another faint slap as a pancake hit the countertop), she was still beaming when she pulled the door open to find Fitz on the stoop. His vague expression of apprehension shifted to something she couldn’t quite place at the sight of her, relaxed as she was sure he’d never seen her before. 

“Fitz! Is everything alright?” Jemma didn’t quite let her smile drop, but wasn’t sure why else the tech-detective would have come all the way out here himself if there wasn’t a problem, especially considering that he generally didn’t seem to have much patience for her. Judging by the police presence at Grand Central when she’d left the night before, she also assumed that he couldn’t have gotten much sleep. 

He blinked at her question and shook his head, clearing his throat. “Yeah, everything’s fine. Sorry, should’ve called – I didn’t think...” Scratching the back of his neck, he chuckled. “My mum would be horrified at my manners.”

Leaning against the doorway, Jemma couldn’t help but grin back at him. Fitz may be notably grumpy – even for a Scot – and he may only have barely tolerated her partnership this past week, but she really quite liked him in spite of herself. His awkwardness was endearing, when he didn’t let it get in the way of being refreshingly intelligent. “Are you sure you didn’t just hope to be invited in to brunch?”

His eyes lit up. “You’re having brunch?” Then he shook his head and she suppressed a small giggle – when was the last time she’d giggled? – as he waved his hand out between them. “I mean, no, that’s not why I’m here.” Letting out what seemed to be a sigh of exasperation with himself, Fitz reached into his jacket pocket and pulled out a familiar evidence bag. “Believe this is yours.”

Jemma reached out to take the small bag from him, her cool fingers brushing against his much warmer ones as she did so. Inside the bag was the enamel broach that had fallen off her jacket the day of that fateful train crash, and she glanced back at him. His head was tilted down, but she could tell he was watching her carefully, and if she didn’t know better she’d think that what flickered behind his guarded eyes was eagerness. Tracing the aquamarine enameling through the plastic, she smiled up at him. “Thank you, Fitz. It was –” She cleared her throat. “This belonged to my mother. I would have been terribly upset to lose it to the 84th’s evidence room.”

Studying her reaction, Fitz nodded, shrugging off her gratitude. “Yeah, thought you’d want it back, so.”

“Is that why you came all the way over here?” Jemma couldn’t help the surprise in her voice; if that was true, the man in front of her was far more enigmatic than she’d given him credit for. There were a dozen different ways he could have gotten the heirloom back to her, many of which didn’t require their interaction, and yet he’d chosen to traipse down to her house on a weekend morning - after a long night’s work, no less. Leo Fitz truly wasn’t your average genius-engineer-detective hyphenate. “Just to return my broach?”

At her question, the slight hint of eagerness disappeared from his face, and Jemma tried to puzzle out what had made him withdraw as he spoke. “Not exactly, no.” Fitz reached into his pocket to check the text that had just buzzed in, and then raised an eyebrow. “There’s been a murder that I was hoping you’d consult on, thought I’d stop by on my way to the scene. It’s a bit of a weird one – and, well, you’re good with that.”

Deciding to put aside examining his reactions for the moment, Jemma grinned. “Yes, I am – must be why we work so well together.” Although she had a moment’s hesitation after the tease was out of her mouth, uncertain as she still was about their standing, Fitz let out a short laugh and her worry eased.

“Yeah, alright, fair play,” he said, his mouth tilted up in a half-smile. “So, you interested?”

“Weird how, exactly?” Instead of responding, Fitz just flipped his phone around to show her the picture he’d presumably just received from his partner, revealing a body that appeared to have been turned to ashy rock. Unable to help herself, Jemma let out a quiet “ _ohhhhhhhh_ ,” wrapping her fingers around his hand to hold the phone steady. “Yes,” she murmured, studying the body’s contorted position. “I am most definitely interested.”

After a few moments, she realized that she was still holding his hand in place and let go, straightening up. As Jemma reached around the doorframe to grab her jacket where it hung, she would have sworn that Fitz’s ears were a shade redder than they had been a few moments ago.

The landline in the entryway rang, then, and she raised one finger to Fitz to indicate that she’d just be a moment, and he nodded. Jacket in hand, she plucked the phone out of its cradle. “Hello?” Jemma paused, listening to the faint static on the other line. “Hello? Is anyone there?”

“Who is it?” Phil called from the kitchen, the sound of cutlery rattling in a drawer as he prepared to set the table.

She waited another few seconds with the phone at her ear, and then shook her head. “Wrong number, I think,” she called back to the kitchen, dropping the receiver back into its old-fashioned cradle. “I’m going out on a case. I’ll text you when I’ll be home,” Jemma said in the general direction of the kitchen, not waiting for a reply before she joined Fitz on the stoop and shut the door behind her.

“Our M.E.’s already there, so you’ll have the supplies you need,” Fitz said as he led her to his car, cherry-light already in place to speed up their drive. Not that there was much traffic in the city at not-quite-ten on a Saturday morning.

Remembering the blueberry-cornmeal pancakes she hadn’t gotten to eat, Jemma felt her stomach rumble as she slid into the passenger seat. “Would you mind stopping for food on the way? I’ll buy, but I’m absolutely fam–”

Fitz chuckled, turning over the motor. “Already planning on it, but I’ll take you up on your offer to buy anyway.”

She laughed, holding up her hands in mock surrender. “I walked into that one.” Glancing at the hard-plastic, black tool case in the backseat, Jemma wondered how long the engineer had been working in the field. Judging by the 84th’s recent establishment, it couldn’t have been for more than a month. “Must be nice to get out of the station sometimes, hm? See something outside of the lab?”

He shrugged, sliding his eyes over when he noticed her scrutiny. “I mean, I like my lab. Good to have someplace that’s yours – and it’s less messy than field work.” There was an almost petulant note to his voice at the last comment, and Jemma suppressed a smile. Fitz said he didn’t have a queasy stomach, but she knew better. “But, yeah. S’not all bad. Sometimes it’s nicer than others.”

If she hadn’t been watching him, she’d have missed the flash of a cringe that passed when he said the last, but no matter what she would have noticed the bright flush that crept into his cheeks. Could he possibly have meant this past week?

“I’d forgotten how much I enjoy working in the field,” Jemma mused out loud, deciding to offer him an olive branch. Maybe he’d decided that he didn’t hate her after all. “The last week has been particularly enjoyable – if messy.” They slowed to a stop at a red light, and she grinned over at him. “I’m glad the 84th needs me again.” 

“Yeah, Trip wasn’t exactly thrilled when I requested you, but the Captain approved right off –”

“You requested me?” Jemma stared back at him, beginning to think that she hadn’t made the slightest accurate estimation of their relationship in the past week.

Fitz’s flush deepened, and he turned his eyes back to the road, the early morning light catching the striking blue pigmentation of his eyes as he did. “Thought we worked well together, s’all.”

More pleased than she cared to parse out, she made a quiet noise of agreement, smiling forward out the windshield. “Not a bad observation – for an engineer.” Fitz scoffed, muttered a quick comeback, and Jemma leaned comfortably back in the passenger seat, thinking that she could very easily get used to running off on adventures like this. Particularly if this intelligent, fascinating, and utterly confusing engineer came along for the ride.

 

\------

 

 _Tonight_  

Not even one drop of blood was left in place of Jemma’s body – the body that Fitz was _certain_ had been there with him. The body he’d checked for a pulse and watched bleed out. Trip and a team of forensics investigators spent an hour with him in the alleyway, but without any visible proof that Jemma had even been in that alley with Fitz, he was left with no choice but to just go home and hope that maybe the crime scene would look different in daylight. His partner offered to treat him to their favorite Chinese place for dinner, but Fitz declined, wanting to go home and dwell on why on earth someone would steal her body, and how they’d done it quickly and quietly enough that he hadn’t even noticed. If he weren’t so confident in what he’d seen, and if he wasn’t a scientist by nature, he might’ve invited the thought that it had to have been done by magic.

As soon as the door of his apartment closed behind him, though, grief consumed Fitz, limbs shaking uncontrollably in anticipation of a panic attack. It had been years since he’d had a real one – years since he’d allowed anyone or anything close enough to trigger one – and rather than deal with it sober, he decided to go after the scotch he’d been saving for his inevitable promotion. Maybe he could knock himself out before desperation truly had him in its clinging, sickly grasp. He was on his hands and knees in front of the small cabinet where he kept his small supply of hard liquor, seeking out tonight’s preferred poison, when a quiet but firm tap sounded against his front door, and he swore under his breath.

Yanking the found Macallan bottle out from behind a rather horrid blue concoction a former girlfriend had once given him, he lurched upwards, ready to give the person intruding on his particular form of mourning a severe talking-to. When Fitz swung the door open as angrily as he could muster, his entire brain slowed, unable to quite accept that Jemma Simmons was not only alive but completely unscathed, and currently standing on the threshold of his apartment.

“I suppose you’ve got a few questions,” she said, giving him a small smile, and his world tilted back into focus.   

The sound of her voice – definitely there and definitely _Jemma_ – sent a jolt of adrenaline through him, and without thinking Fitz stepped forward and slanted his mouth hungrily against hers. She made a small noise of surprise but melted almost instantly into his touch, her tongue darting out to glide against his lips before it could occur to him to do more than just drink in the solid feel of her there with him, alive and real. Breath hitching at her response, he gave himself over to the kiss, angling her mouth open and finding that the taste of her was even better than in his dreams. His hands made their way up to her neck, gingerly tilting her head back so he could step closer, her arms wrapping firmly around his waist. The slide of her tongue against his made warmth radiate through Fitz’s entire body and she released a small gasp when he traced his thumb down the skin of her neck, reminding himself that Jemma was alive and not dead, she had a pulse and was here in his arms, and she was kissing him back.

Eventually, what felt like much to soon Fitz needed to pull away to catch his breath, leaning his forehead against hers as they both gulped in air.

“Oh,” Jemma breathed against his lips, honey-brown eyes staring into his own, and he shivered as her fingers scratched through the short, rough curls at the back of his neck. “Perhaps you didn’t need that explanation after all.”

“No, I bloody well do,” Fitz murmured, giving her two more quick-but-heated kisses, his heart still racing out of surprise, excitement, and pure joy. “I’m just so...”

“Surprised?” Her smile was sad, almost resigned, and he pulled just far enough away that he could see her properly.

“Relieved.” In truth, he thought that every synonym for “happy” in the English language wouldn’t be able to describe what he was feeling right now, but he opted for the most important one. “That I didn’t miss my chance.”

Jemma wrinkled her nose in slight confusion, settling her hands against his chest. “For what?” 

“For –” Fitz faltered, certain that responding with something like _for you_ would sound both clichéd and asinine, its accuracy notwithstanding. “– for this. To ask you to dinner, or coffee, and all that.” 

She gave him a smile that seemed to suggest she knew what he’d really meant despite his clumsy attempt to downplay it. “Doesn’t dinner traditionally come before this?”

“I watched you die two hours ago and now you’re standing in my apartment,” he retorted drily. “I doubt tradition has much to do with whatever we are.”

“Excellent point,” she chuckled, unconsciously straightening his collar where she’d disarranged it.  “Um, could we, maybe, go inside? Time for that explanation, I think.”

He stepped away, gesturing for her to enter, and she made straight for the couch while he shut and bolted the door. After grabbing the scotch bottle – that he didn’t even remember dropping – and placing it on a table, Fitz turned to see Jemma curl primly onto the sofa, pulling her cashmere cardigan more tightly around herself. “Are you cold? I can get you a blanket –” But he stopped when she shook her head, gazing fondly back at him. 

“No, thank you. Just – come here. Please.”

Jemma held a hand out and he reached for her automatically, that feeling of pure happiness yet again radiating outwards from his chest as he allowed her to pull him right against her on the sofa. Taking a deep breath, Fitz brought her hand up, pressing his lips against her knuckles, his curiosity slightly dulled by the fact that 90% of his brainpower was still focused on the fact that she was alive and here with him, and nothing else mattered as much as that.

 

\------

 

When Fitz pressed his lips to the back of her hand, Jemma couldn’t stop the tremulous smile that spread across her face. Instinctively seeking out more of the surprising, fascinating heat that built between them in the doorway, she slipped her hand away to curl around his neck, bringing his lips back to her own. This time she took the lead, gently coaxing his mouth open and reveling in the way this initiated a groan low in his throat. His hand found purchase in her damp hair, flexing his fingers as she teased his tongue with hers. It had been a long time since Jemma had wanted to be this way with the _person_ rather than just needing to take care of her biological needs, and Fitz was proving to be far more skilled at this particular activity than she would have thought.

Which is not to say that she’d thought he would be poor at it – just that she hadn’t really thought about him in that way until tonight, although she was rapidly realizing that this explained a lot of her own behavior in the past few months. Fitz was the first person she could imagine herself really, truly falling for in over a century and a half, and it was happening so much faster than she would have expected.

At the unbidden memory of _why_ she hadn’t allowed herself to feel the way she did right now in all that time, however, the excitement and eagerness drained out of kissing him, his lips and his touch suddenly a symbol of exactly what she would inevitably lose. So she pulled away, trying to get her breathing back to normal before she tried to speak. 

“Sorry. Got, um, distracted,” she squeezed out, trying to make herself look somewhere other than his lips.

“I’ll try to make myself less desirable,” he deadpanned, his own breath still shallow. “Make it easier for you to keep your hands off me.”

Jemma grinned, but forced herself to lean back, grabbing hold of her leg to keep herself from reaching for him again. “What I’m about to tell you may seem... well, more than a little insane. And scientifically impossible. But I swear, Fitz, it is all true.” He nodded solemnly, turning so that he could face her more comfortably on the couch.

For what felt like hours to Jemma but could only have been a few minutes, she explained to him that she’d first died not-quite two centuries before. Explained how someone shot her as she worked at her hospital, that she fell out of the window behind her and landed in the adjacent river, and that she’d been “reborn” in water every time she’d died since. Told him how she lived an almost-nomadic life, only staying in one place until her carefully utilized makeup couldn’t conceal her perpetual youth any longer. That Phil was actually an adopted son she saved from a negligent orphanage, and he’d stayed with her for longer than anyone else ever had. 

When she finished, Fitz just nodded slowly, chewing on his bottom lip as he considered her story. 

“So... you’re going to live forever.”

She couldn’t help but give a slightly derisive snort. “Forever is really a rather ambiguous concept.”

He rolled his eyes, sliding his fingers over to tangle between hers. “Yeah, alright, but –”

“For all intents and purposes, I am immortal, yes.” Jemma cringed inwardly at that word, especially considering that immortality often implied not being able to be killed and she couldn’t even count how many times she’d died by this point – but it was more succinct and closer to being accurate than anything else.

“That’s really bloody amazing,” he breathed, shaking his head in wonder.

Jemma let her lips curl upwards slightly at his words; he was so young, and so human. Even she had once thought of this never-ending life as a gift – but she’d long since learned that being frozen in time was not the blessing it appeared. 

“Not when you’ve lived as long as I have,” she whispered.

The way his brows furrowed at her words made her want to kiss him senseless again, and she resisted the urge to shake her head at herself. Somehow, now that her feelings about Fitz had been made clear to herself, every tiny movement he made seemed that much more endearing, and if she was going to ever force herself to halt this relationship in its tracks she had to stop thinking that way.

“D’you... d’you wish you’d died?” His words were quiet, his sudden, unnatural stillness making her chest constrict. 

“No,” she answered, squeezing his fingers gently. “Not right now, anyway. I just... I want to live the rest of my life, and let it end where it may. I want to settle down without worrying about hiding my secret. I want to be able to grow older –”

His shoulders loosened at her words, and he chuckled, interrupting. “You _want_ to turn into a wrinkly old hag?”

“At least it would be something different.” Her tone was light, belying her desperate wish to return to that kind of normal life.

“To be honest, I’m just glad I don’t have to worry about you anymore when we’re out on a case. Tonight was...” Fitz licked his lips, searching for the right phrasing. “I don’t want to do that again.”

The way he said the last part was stiff, his accent cutting off each word sharply, and she raised a hand to smooth her fingers over the redness that lingered around his eyes. He would probably never admit it, but he’d certainly cried at some point before she showed up, and she felt a strong twinge of pain at the idea that she’d caused him to do so. Jemma dropped her head, forcing herself to squeeze out the words she really, _really_ didn’t want to say.

“I’m sorry about tonight. I am. But... I’m afraid we can’t do this. Be a ‘we.’ Even if I _do_ want to. Very much.”

The hurt that flashed across his face disappeared at the last few words, and he smiled, reaching up to smooth his knuckles against her jaw. “Just ‘cause of the age difference? I don’t mind the cougar thing, honestly.” Fitz’s voice had returned to a normal, teasing tone, but Jemma couldn’t go back there, not yet. Not until she’d made him see the problem.

“You don’t understand, Fitz.” 

“Leo.” He cleared his throat, cheeks reddening. “If we’re – you should call me Leo. If, I mean, if you want to,” he stuttered out, shaking his head at himself and making a distinct warmth bloom within her chest. 

“Oh,” she whispered, pressing the palm of his hand to her cheek, closing her eyes against the sadness that was threatening to burst out. “ _Leo_. I’ll be the same to you for the rest of your life. When you’re seventy, I’ll still look like this, sound and think like this. But you...” Jemma forced herself to open her eyes and meet the warmth of his darkened blue gaze.

“I’ll have to watch you deteriorate, just like everyone else. Everyone but me. Your coordination will likely go first, meaning that you couldn’t make your machines yourself anymore. Your voice will weaken, and your hands will shake. Then your cognitive functions will start to fail, slowly, almost imperceptibly, until you’ll be hunting for a word that used to seem so simple but now won’t come at all. And one day you’ll just be gone.” She inhaled sharply, trying not to break eye contact but finding it harder the longer she spoke. “I’m not strong enough to watch that happen to you, Fitz – Leo. I’m so sorry, but I’m not.”

As she managed to force that last word out, her voice broke and she dropped her face into her hands, out of frustration as much as sadness. She’d had to learn to live on past the death of many people she’d cared for over the past two centuries – you couldn’t live as long as she had and avoid it, if you didn’t want to be completely alone. Time went on and she’d made herself become hard, worked to shut down the guilt that would have kept her from moving on, kept her from continuing her search for a cure. But somehow the thought of this happening to this man, this engineer and tech genius she’d met barely six months ago, was wringing her heart in a way she couldn’t suppress or control, kicking in her instinct to cut and run. Knowing that she’d eventually lose her adopted son to time was bad enough – she couldn’t bear to watch it happen to two people she loved in one generation.

Two warm hands cupped her jaw, forcing her head up again towards Fitz. His stare was somehow both soft and intense, and she wondered once again at how this felt so natural, even though the feelings they were discussing were far beyond what could logically exist after only six months of partnership and five minutes of rather heated kissing. 

“D’you remember what Trip said about us during our second case?” Jemma wrinkled her nose, thinking, and then shook her head. “That we were twice as –”

“Oh! Yes,” she interrupted. “That together we were twice as smart.”

He smiled fondly, brushing a thumb over her cheekbone. “Yeah. You’ve been studying – well, yourself, for decades, but maybe now we’ve got the right technology. And I’m pretty good with tech, if you hadn’t noticed.”

“Pretty much a genius, in fact,” she teased, allowing her lips to turn up at the corners.

A faint flush flared around the edges of his ears at the compliment. “So maybe I could help. Maybe we can find a solution together. Either find a way to restart your aging, or I could try...” Fitz trailed off, leaving the offer unsaid, and she shook her head vehemently.

“You don’t want to live forever, Fitz. It’s not enjoyable – take it from someone who knows.” 

He shrugged, sliding his hands down her arms to gather her hands into his. “Might not be so bad, if I’m with...”

 _You_ , she almost finished for him. The word hung between them, unspoken but both well aware of what he meant, and Jemma pressed her forehead gently against his. “Okay,” she whispered, curling one hand around his neck, shivering at his almost unnatural warmth in comparison to her still-chilled limbs, the cold of her damp hair seeping through the rest of her body. “Let’s see if we can fix this.” 

“Together,” he added, leaning forward to close the space that lingered between their lips.

Yes, Jemma thought as she wound her arms around Fitz’s neck, allowing herself to forget about the problems that lay ahead and focus on the press of his body against hers. _Together_ had a rather nice ring to it.

**Notes for the Chapter:**

> Voila! I've got a sequel planned, but it's in the early stages. No idea when that'll be up - but hopefully this installment feels complete enough that no one's jonesing for more too badly. :-)

**Author's Note:**

> Thank you so much to MK for editing & soothing my neuroses!


End file.
